Drag reduction by polymer additivers in a turbulent pipe experiments

Characterization and Identification of Bituminous Materials Modified with Montmorillonite Nanoclay

Montmorillonite (Mt) nanoclay is a layered silicate mineral with a 2:1-type layer structure, two tetrahedrals sandwiching one octahedral. In recent decades, it is successfully introduced into polymer systems to form polymer-clay nanocomposites (PCN) in which the silicate layers of the Mt are randomly and homogeneously dispersed at a molecular...

Flow of polymer solutions through porous media

These days leading oil and gas producing companies are investing increasing amounts of money into the development of non-fossil energy sources like wind-, solar-, biomass energy and forestry. On the other hand these companies are persisting in developing techniques to make energy recovery more efficient intending to stretch the life span of...

Shallow-earth rheology from glacial isostasy and satellite gravity: A sensitivity analysis for GOCE

In recent years, satellite gravity missions have been launched that probe the earth's long- to mediumwavelength (1000 - 500 km) gravity field. The upcoming ESA satellite gravity mission GOCE is predicted to measure the gravity field with an accuracy of a few centimeters at spatial scales of 100 km. Such a high-resolution gravity field contains...

Double-curved precast concrete elements: Research into technical viability of the flexible mould method

The production of precast, concrete elements with complex, double-curved geometry is expensive due to the high costcosts of the necessary moulds and the limited possibilities for mould reuse. Currently, CNC-milled foam moulds are the solution applied mostly in projects, offering good aesthetic performance, but also resulting in waste of material...

The effect of aging on binder proporties of porous asphalt concrete

In this dissertation, the results of a research on the effects of aging on the binder properties of porous asphalt concrete (PAC) are described. The research has been done on laboratory and field aged specimens. In addition to the conventional aging methods for short and long term aging of the binder in the laboratory, a new mixture aging...

Rheological properties of olefinic thermoplastic elastomer blends

Thermoplastic Elastomers (TPE) are a class of materials that have rubber-like properties and can be processed like thermoplastic polymers. In this thesis, the rheological properties of two TPE blends are correlated to their morphology. The thermoplastic vulcanisates (TPV) consist of micron-sized, cured elastomer particles while the blends of PP...

Dynamics of foam in porous media

Megathrust Earthquakes: Study of Fault Slip and Stress Relaxation Using Satellite Gravity Observations

During earthquakes large scale mass displacements take place when slip on a fault deforms the earth’s crust. Besides, in the days to decades after the main shock ongoing deformation is usually observed that is related to relaxation of stresses caused by the earthquake. In this thesis I relate gravity changes as observed by the GRACE satellite...

A rheological and structural study of polymer networks

Rheological Analysis of Mud: Towards an Implementation of the Nautical Bottom Concept in the Port of Hamburg

The nautical bottom (the level at which contact with a ship’s keel causes either damage or unacceptable effects on controllability and manoeuvrability of a ship) should be associated to a measurable physical characteristic. Bulk density is typically used as a criterion for nautical bottom by many ports worldwide. However, the rheological...

Response of DNA molecules to external fields: Electric and hydrodynamic

Elastic Instabilities in Polymer-Solution Flow Through Porous Media

Crude oil has been an important source of energy for several decades now. Upon discovery of a crude oil reservoir until its abandonment, typically the oil recovery process can be classified in three stages. The primary and the secondary stage involve utilizing and maintaining reservoir pressure to recover oil respectively. The tertiary, or the...

Magnetic fluid bearings & seals: Methods, design & application

The bearing and the seal are two commonly used tribological components since nearly all moving machinery relies on them for proper operation. Even a small improvement in these components can have a big impact on both the market and the environment. The two main problems of these components are wear and friction. In addition, seals suffer from...

Transient mechanics of foams and emulsions

Systems far from equilibrium have numerous practical uses, but challenge our understanding of their underlying physics. Materials like foams, emulsions, suspensions and granular matter can show liquidlike properties or get trapped in a solidlike jammed state. The phase transition between the flowing and static state is often referred to as the ...